Should there be a Sequel to Prometheus?

Random sketches of David 8 from 'Prometheus'.

I was bored - it's been how long since the film came out and I'm still trying to figure it out. I've also started trying to guess at the possible sequel's plot. Had an image in my head regarding David 8 and how they'll probably have to have his head put back on when the time comes - how else could they have him as a main character? He certainly shouldn't spend the length of the film as just a decapitated head . . . should he? I mean, they attempted to travel down that route with poor Bishop in Alien 3 and look where it lead to.

At any rate, I do wonder where the sequel will go. So far I've leveled it down to just the two possibilities (the logical ones, I mean).

1) A deep-salvage team is sent out to find the Prometheus. David and Dr. Shaw will likely not be main characters. Instead of finding the Prometheus, they find the Engineers, the aliens, the black ooze, and this time we have something more liken to the xenomorphs we're so familiar with. Then again, Ridley Scott has explained that the sequel (if there is one) will veer even farther away from Alien then Prometheus did. So when I say 'xenomorphs' I mean the dolphin-looking creature that burst it's happy little way out of the last remaining Engineer's chest at the close of Prometheus.

2) The film revolves ENTIRELY around David and Dr. Shaw. That Shaw fixes David shortly after their take-off, and that he then puts her into cryo-stasis on board the Engineer's ship. When she next wakes, a multitude of years has passed - decades even - and they find themselves either on a new Engineer world (the home world perhaps), or taken in by another humans hip. Perhaps they are accidentally discovered by a deep salvage team or a ship full of colonists on their way to terra-form a planet. Scott has also claimed that the Prometheus sequel would run parallel to the Alien films if it were to be made - so when I say 'terra-formers' I mean around the time Weyland/Yutani is 'Building Better Worlds' like in Aliens.
Just some musings of mine.

What are your thoughts on a possible Prometheus sequel?

Do you suppose one will get made? If so, what do you reckon the plot would be?

Would the story revolve around Shaw and David - if so, how?

Do you think Scott should even attempt a sequel if it's only going to run parallel to the Alien films and not truly explain them?  Do you think a sequel would ruin the credibility or delightfully confusing nature of Prometheus?

Feel free to share your thoughts. These are big queries . . .